1. Field of the Invention
The invention relates to an upper tool support for a stamping machine or the like having at least two stamping tools adjacently located. Each stamping tool preferably includes a punch, a punch support and a retaining nut connecting the punch with the punch support. The upper tool support is provided with a support body, a receiving plate with tool guides for each stamping tool disposed next to each other in the receiving plate, and a locking cap. The locking cap is connected to the support body to be pivotable around a pivot axle, and is thus pivotably removable from the support body in a plane perpendicular to the direction of stamping. Upper ends of the stamping tools are movably guided in the direction of stamping, and limited for motion in this one direction, by support flanges from the support body.
The following explanations basically relate not only to the upper tool supports of machine tools in the form of stamping machines, but also, for example, to cases where two or more ratchet-driven tools are disposed next to each other. The teaching of the invention thus is not limited to a stamping machine and to stamping tools, but applies to all machine tools in which comparable problems exist. In order to facilitate the understanding of the teaching, the teaching of the invention is described here and below by means of the preferred exemplary embodiment of an upper tool support for a stamping machine.
2. The Prior Art
In the known upper tool support for a stamping machine or the like which is the background art out of which the present invention arises (EP-A-O 180 146), a quick change of a stamping tool and/or of all stamping tools is possible, taking into consideration the limited space where several stamping tools are located next to each other. If the receiving plate is a part of the support body, and if the tool guides are open in for instance the horizontal direction towards the front of the support body, then the upper ends of the stamping tools can be generally pushed into or placed horizontally in the tool guides. The locking cap locks all tool guides together at the open ends. By means of application of the locking cap which is then locked, the open ends of all tool guides in the receiving plate are locked in one step. Thus all stamping tools are secured. For this purpose the individual ends of the stamping tools are provided with hammerhead-like enlargements, and the receiving plate and the locking cap are provided with support flanges corresponding to the hammerhead-like enlargements, so that the stamping tools cannot slip downwardly out of the tool guides. The locking cap is pivotably fastened on the support body, or to the receiving plate, via a pivot axle and is lockable with the support body (or the receiving plate) by means of a locking device disposed on the opposite lateral side. The locking device has a locking bolt pivoting in the horizontal plane on the receiving plate and a bolt receptacle provided on the locking cap and open on one side. The locking bolt is pivotable into the bolt receptable, and fixable therein by means of an adjusting nut for locking. Furthermore, receptacles for the upper ends of the stamping tools are provided in the support body above the tool guides and below a power transfer area, and these receptacles can be bridged by means of power transfer rods generally movable perpendicularly to the stamping direciton. With each stamping tool is associated a lifting lever, one end of which laterally engages the upper end of the associated stamping tool from below, so that the upper end of the stamping tool can be lifted into the receptacle by means of the lifting lever when the power transfer rod is pulled back. Pneumatic drives or the like, not further described, are provided for this purpose.
The upper tool support previously described and forming the background for the teaching of the present invention cannot, for all practical purposes, be improved in regard to the quick exchangeability of the stamping tools. However, it has been shown in practice that the half shell design of the receiving plate and the locking cap for forming the tool guides has its problems. If the locking device is overly tightened, the stamping tools possibly become wedged in the tool guides. This prevents the upper tool support from functioning, and gives rise to the possibility of damaged stamping tools or even of other parts of the machine being damaged.